Woven and non-woven fabrics are well known fibrous materials for use in floor coverings such as carpets, carpet tiles, rugs and the like. It is also known to provide certain floor coverings, especially the non-woven types such as felt or tufted floor coverings, with an integral backing layer to protect the floor covering against wear and to improve its dimensional stability. It is important that these floor coverings having integral backing layers be sufficiently flexible to prevent cracks forming in the backing layer during transport, storage and laying operations. Further, after laying the backing layer must be able to withstand heavy loads without the surface remaining indented for an undesirable length of time after the heavy load has been removed.